Notice That There Are Not Many Survivors of the MC from the early 19080's or so?

Every once in awhile I will see an odd Audioquest 404 for sale. But otherwise not too many cartridges from this generation. I have always wondered about whatever happened to the Sumiko SHO cartridges. Were they the predecessor to the Blue Point or the Blackbird? Always wondered how they sounded, never got to hear one. 

I wonder if it is the use of the hollow rod cantilevers that caused them to become lost cartridges. I don't think you could retip them, but the best you could do is trade them in for a discount. 

The other cartridge I see from time to time are the Shinon, and every once in a great while I will see one come up for sale. Oh an odd Ortofon or two, and that is about all I remember for this era of moving coils ever coming available.